Despite dramatic gains in women?s educational attainment globally, the pace of decline in fertility and child marriage is slower than expected in some countries, raising the question: Under which conditions is women?s education most likely to translate into delayed marriage and lower fertility? A voluminous literature exists on the links between grade attainment and reproductive behavior in the developing world. In contrast, much less is known about the effect of academic skills, both the absolute level and the change in the level, on the timing of marriage and childbearing, in part because researchers have had to rely on cross-sectional data where skill level ? typically literacy ? is measured after the outcomes of interest and grade attainment is used as a proxy for skill level. Further, there appears to be no research in low-income settings on the effect of early marriage and pregnancy on the retention or loss of academic skills. Understanding the bidirectional relationship between academic skills and reproductive behavior, particularly for adolescent girls in low-income settings, who may experience rapid transitions from student to adult roles, will inform more effective interventions both to improve adolescent and adult literacy and numeracy, and to delay marriage and prevent adolescent pregnancy. Using recently collected longitudinal datasets from three low-income settings?Malawi (N=1337), Zambia (N=5241), and Bangladesh (11617), the latter two of which include cluster-randomized controlled trials, the proposed study will contribute to our understanding of the links between academic skills and reproductive behavior among adolescent girls by addressing several key issues: 1) how academic skill levels change during adolescence and factors that contribute to gain or loss; 2) whether there is a minimum level of grade attainment that protects against skill loss; 3) the extent to which skill level, and change in that level, affects the timing of the first reproductive event; 4) the extent to which early marriage and childbearing contribute to loss of academic skills; and 5) the conditions and interventions that promote skill acquisition and retention among vulnerable adolescents. While it is rare to have longitudinal data on skill level combined with data on the timing of marriage and childbearing, it is even rarer to have such data in multiple settings. The analytic sample will be limited to those girls who were enrolled in school and had not yet experienced a first reproductive event (marriage or pregnancy) at baseline. In addition to taking advantage of the cluster-randomized controlled trials embedded in AGEP and BALIKA, we will use instrumental variable analysis and fixed effects models to minimize potential biases in our results due to endogeneity. The proposed study will greatly expand the knowledge base on the causes and consequences of learning retention in sub-Saharan Africa and South Asia, two regions where, despite increasing access to schooling, large numbers of adolescents lack basic skills needed to lead productive and healthy lives.